Cooper’s hawks are good-sized birds, distinctly smaller than a red-tailed hawk but about the size of a crow. Compared to either of those familiar species, though, a Cooper’s hawk creates a distinctly different impression — lanky, long-tailed, and somehow loose-jointed. Cooper’s hawks spend much less time soaring than red-tails do, though the smaller hawk is perfectly capable of riding a thermal up until the bird is just a pin-point. But in level flight, a Cooper’s hawk is much more businesslike than either of those other species, zipping along without the dallying of a crow or the slow, lumbering wingbeats of a red-tail.
If you get a decent look, the only thing you can confuse a Cooper’s hawk with is its smaller relative, the sharp-shinned hawk. The two raptors come close to overlapping in size: A small male Cooper’s is just a hair larger than a big female sharp-shin. But ornithologists assure that Cooper’s is reliably, if sometimes just marginally, larger. Sharpies are also more compact in build, flying with a distinctive, wrist-flicking wing stroke that is quite different from a Cooper’s deep wing beats that seem to move only the shoulder joint. Sharp-shins do not nest on the Vineyard, so confusing these species is not an issue in the summer. And in recent years, at any season, sharpies have averaged somewhat less common than Cooper’s hawks.
Getting that decent look at a Cooper’s hawk is by no means a given. To be sure, the species sometimes sits tamely on a perch, often allowing a fairly close approach. And while patrolling or traveling, a Cooper’s hawk may interrupt its generally direct flight with loops or swoops to check out a promising thicket. But the classic sighting of a Cooper’s hawk, every time you experience it, will remind you why these are such effective hunters.
The arrival of a Cooper’s hawk may be heralded by a sudden, eerie silence if other bird species have been vocalizing; with sharper vision than you, and a lot more reason to stay alert, songbirds often detect an incoming Cooper’s hawk and dive for cover. To more obtuse human senses, a Cooper’s hawk often materializes as a dark, elongate streak, moving faster than seems quite believable just above the prevailing level of the vegetation. A moment and a few sharp turns later, the agile hunter disappears from site.
Unless it spots an opportunity. The point (from the hawk’s perspective) of this darting, low flight is to startle a smaller bird into a panicked take-off. The hawk is constantly looking for precisely this, and when a surprised sparrow or chickadee pops up, the hawk carves as steep a turn as is needed to get the smaller bird into the crosshairs. As often as not, it connects, its powerful talons snagging the smaller bird in mid-flight.
It would be hard to overstate the importance of this low-level hunting strategy to a Cooper’s hawk, or to exaggerate the adaption these hawks show to their preferred method of assassination. Cooper’s hawks, if they remain in an area for any length of time, rapidly acquire a detailed “resource map,” pinpointing thickets, water sources, feeding stations, and other locations where a concentration of food or shelter produces a concentration of songbirds. A Cooper’s-in-residence rapidly develops a daily route around its hunting territory, often working each hotspot on a regular schedule. Buzzing each likely spot, the raptor is almost certain to get a few chances to score.
It isn’t just this astuteness that makes these birds effective, though. Cooper’s hawks, like all raptors, have astonishingly sharp vision, and lightning reflexes to go with it. And the hawk’s long tail — really a rudder — and short, strong wings translate to an unbelievable ability to maneuver sharply. I’m sure it’s impossible, under the laws of physics and aerodynamics, but I get the impression that a Cooper’s hawk, even at full attack speed, can reverse direction in barely more than its own body length. The tail twists, one wing goes up and the other goes down, and instantly the hawk is on a new heading.
Our local Cooper’s hawk has been spending lots of time lately perched in a tall catalpa tree across the street. The perch overlooks the neighbors’ aviary: The chickens and ducks there are safely enclosed, but clearly the Cooper’s hawk remains optimistic (these hawks, with justification, are sometimes known as “chicken hawks,” and the fact that a chicken may outweigh the hawk doesn’t deter the raptor one bit).
After a while, concluding that domestic fowl is once again not on the menu for the day, the hawk drops out of the catalpa tree and darts off to patrol the rest of its route. There are pigeons around, and house sparrows, and chickadees. And every day, two or three of those smaller birds will find itself in the talons of this proficient aerial hunter.